It is known that a metal salt of a salicylic acid compound can be used as an electron-accepting compound in recording materials using a combination of an electron-donating colorless dye and an electron-accepting compound, as described, for example, U.S. Pat. Nos. 3,864,146, 3,983,292, 4,134,847, 4,234,212 and 4,289,332, and JP-B-58-38ll8 (the term "JP-B" as used herein means an "examined Japanese patent publication").
Known processes for preparing a zinc salt of a salicylic acid compound include methods in which a salicylic acid compound or its alkali metal salt is reacted with a zinc compound in water or in the absence of a solvent. However, these conventional methods were not satisfactory in workability or yield or purity of the product.